Valve actuating mechanism



y 1940- L. R. SPENCER 2,209,479

VALVE ACTUATING MECHANISM Filed June 7, 1938 I Qwucnbom Low 2L RSpenQcr,

Patented July 30,1940

PATENT OFFICE VALVEACTUATING MECHANISM Louis B. Spencer, West Hartford, Conn., assignor to Spencer Aircraft Motors, 1110., Hartford, Conn, a corporation of Connecticut Application June 7, 1938, Serial No. 212,346

4 Claims.

This invention relates to improvements in actuating mechanisms for the valves of internal combustion engines.

One object of the invention is to provide a valve-actuating mechanism of simple construction in which adjustments can be readily made for purposes of providing proper clearances or for compensating for Wear.

A further object of the invention is to provide a valve-actuating mechanism comprising a rocker arm or lever carrying a valve-stem-engaging member but with which a series of members may be interchangeably used, the several members being of diiferent sizes to compensate for wear or to provide proper adjustment of the mechanism with respect to the valve stem and the cam or other operating element by which the arm or lever is rocked.

A still further object of the invention is to provide a valve-actuating mechanism comprising 'a valve-stem-engaging member securely attached to its rocker arm or lever, but from which arm or lever the member may be readily removed to permit replacement thereof with a new valvestem-engaging member.

Another object is the provision of a valve-stemactuating mechanism in which the moving parts are efficiently lubricated.

More specifically, the invention contemplates a valve-actuating mechanism comprising a rocker arm or lever carrying the valve-stem-engaging member, said member consisting of a substantially circular disc-like element seated in are cess in the rocker arm, the size and shape of said member and recess being such that a major portion of the periphery of the disc is embraced within the recess. In other words, the walls of the recess extend around more than half of the disc and the diameter of the disc is greaterthan the length of the entrance to the recess, so that, normally, the disc is securely held in the rocker arm. However, a portion of the periphery of the disc is flattened to form a valve-stem-engaging surface and, by rotating the disc in the recess to position the portion with the reduced over-all dimension in the entrance to the recess, the disc can be readily removed.

With these and other objects in view, the invention consists in certain details of construction and combinations and arrangements of parts, all as will hereinafter be more fully described, and the novel features thereof particularly pointed out'in the appended claims.

In the accompanying drawing Figure 1 is a vertical sectional view taken longitudinally of the valve stem, but showing the stem and rocker arm or lever in elevation;

Fig. 2 is a similar view, but somewhat enlarged, showing the rocker arm and valve stem in their depressed positions, in dotted lines;

Fig. 3 is a bottom plan view of the rocker arm and valve-stem-engaging member, this View being taken in the plane indicated by the line 33 of Fig.2;

Fig. 4 is a transverse sectional view on the 10 line 4-4 of Fig. 2; and

Figs. 5 and 6 are elevationa l views illustrating different sizes of valve-stem-engaging members. Only the upper portion of the casing it) is illustrated and, as the latter does not form any part of the present invention, a detailed description of the same is unnecessary. As is customary in structures of the present type, the valve stem H is yieldingly urged upward by one or more coiled springs l2 surrounding the same 20 and engaging against the under surface of an enlargement I3 mounted on the upper end of the valve stem. The valve stem is illustrated in Fig. 1 in its upper position, this being the position occupied by the stem when the valve is closed. To depress and open the valves in proper F1 timed relation with. one another and with respect to the ignition system, a cam shaft I l pro vided with a series of cams i5 is revolubly supported in the upper portion of the casing. Each cam I5 is adapted to engage and depress a rocker he arm or lever 5 which, in turn, is adapted to depress valve stem H, said arm or lever It being provided with what, for convenience, has been termed a valve-stem-engaging member ll.

of a number of diiierent-sized valve-stem-engaging members, a feature that is desirable in connection with the proper original adjustment, so to speak, of the rocker arm with respect to the valve stem, and in connection with replaceas at !8, this flattened portion being adapted to engage against the fiat upper endface of the valve stem II. By reason of the formation of the flattened surface l8, each member I! might be said to have a major and a minor over-all di- In order to facilitate the interchangeable use ment ofworn valve-steni-engaging members, the

mension, the minor dimension being the distance between the flat surface I8 and a diametrically opposite point on the periphery of the disc, while the major dimension will be the normal diameter of the disc or the distance between diametrically opposite points on the periphery of the disc in a line parallel to the flat face l8. It should also be here noted that, while the diameters of the circular portions of the discs are identical, nevertheless the several discs of a series can be of different minor dimensions by removing varying quantities of metal from the individual discs in forming the flattened surface I8. Thus a series of these graduated discs can be used to compensate for differences caused by wear either on the cams 45 or on the end of the valve stem H.

For securing the valve-stem-engaging member in the rocker arm or lever 16, the latter is formed at its free end with a recess of a shape corresponding to and adapted to receive and embrace a major portion of the circular section of the disc ll. By having the recess accommodate a greater portion of the disc, so that the walls of the recess extend more than half way around the disc, the latter, while in such a position, cannot be removed from the recess. However, as will be appreciated, the entrance to the recess is at least as large lengthwise as the minor dimen sion of the disc so that, if a disc is turned to a position where its minor dimension is in registry with the entrance to the recess, the disc can be slipped into the recess and, then, by rotating the disc in the recess, the flattened surface can be moved around until it is located exteriorly of the arm in a plane parallel to the end face of the valve stem. To prevent accidental rotation of the disc in the rocker arm recess, a cross-pin I9 is preferably provideol.v In other words, with the pin l9 inserted, the disc cannot be rotated but, by removing the pin l9 from the disc and arm, the disc may then be rotated to again position the minor dimension of the disc in the entrance to the recess, whereby the disc can be removed and a new disc inserted to compensate for any adjustments that might be necessary.

In order to accommodate any relative movements between the disc I! and the arm 16, the pin l9 preferably fits somewhat loosely in the disc, so as to permit a rocking movement of the disc. Thus, movement of the arm up and down, as indicated by the dotted lines in Fig. 2, does not interfere with the flat seating of the surface IS on the surface of the valve stem, nor does it effect any substantial relative movement between the contacting surfaces of the disc and valve stem. Consequently, wear at this point is reduced to a minimum. Preferably, means are also provided for lubricating the surface of the disc I! in contact with the wall of the recess in the arm [6. For instance, the cam shaft [4 may be provided with an axial bore 20 serving the purpose of a lubricant reservoir, from which lubricant may escape through a duct 2| in said cam shaft once each revolution of the shaft, this flow of lubricant occurring when the duct 2! extends downwardly in moving into and out of contact with the upper surface of the arm I6. Likewise, arm I6 is provided with a duct 22 located in alinement with a duct 2|, so that each time the duct 2i passes over the duct 22, a small quantity of lubricant will be fed down into the interior of the recess in the arm where it will flow between the contacting surfaces of the recess and disc.

As previously explained, the discs in any given series of discs will be of different sizes so far as concerns the distance between the fiat surface I8 and the diametrically opposite point on the disc, so that in the original installation of a disc, the proper-sized disc can be used to permit proper seating of the valve when the latter is in closed position. Due to the ease with which discs can be slipped into and out of the recesses in the arm, one or more discs can be readily placed in the arm until the proper adjustment of the valve stem and valve is obtained. Likewise, when undue wear has occurred and it becomes necessary or desirable to replace a disc, it is a very easy matter to remove a disc then in the arm and replace it with another disc of the proper size. It might be added, although it will be readily appreciated, that this removal and replacement of discs in an arm does not involve any deformation of the material of which the arm is made. That is, there is no necessity of upsetting or spinning over the material at the entrance of the recess in securing a disc in the arm and, hence, the replacement of discs does not entail destruction or deformation of any part of the arm.

What I claim is:

l. A valve-actuating mechanism comprising a rocker arm and a valve-stem-engaging member carried thereby, said arm having a recess therein formed with an elongated entrance, the length of said entrance being less than that of the interior of the recess, and said member being of disc-like formation but formed with a major and a minor over-all dimension, the minor dimension of said member corresponding to the length of the entrance to said recess, and said member being rotatable in said recess to position said member with the minor dimension thereof in registry with said entrance whereby said member can be removed from said recess, and a removable locking pin engaging the member for permitting only oscillatory motion of said member in said recess.

2. A valve-actuating mechanism comprising a rocker arm having a recess therein and a valvestem-engaging member of substantially circular disc-like formation, the major portion of said disc being embraced by but rotatable in said recess, and a locking pin extending into said recess permitting only oscillatory motion of the disc in said recess, said disc being removable edgewise from the recess in the absence of said pin.

3. A valve-actuating mechanism comprising a rocker arm having a recess therein and a valve-stem-engaging member of substantially circular disc-like formation, the major portion of said disc being embraced by but rotatable in said recess, said disc having major and minor over-all dimensions with the minor dimension substantially corresponding to the entrance of said recess in the arm, whereby rotary motion of the disc to position the same with its minor dimension in registry with said entrance will permit removal of the disc edgewise from said recess, and a removable retaining pin extending through the arm and disc normally permitting only oscillatory motion of the disc.

4. A valve-actuating mechanism comprising a rocker arm having a recess therein and a valvestem-engaging member of substantially circular disc-like formation, the major portion of said disc being seated in and embraced by said recess,

said disc being rotatable in said recess for removal edgewise therefrom, and a pin extending through said arm and disc, said disc being capable of a rocking motion on said pin.

LOUIS R. SPENCER. 

